Figure 5.

Sequence alignment of VirB10_CTD shown for the conjugation plasmid pKM101 T4S system (TraF), bacteria-killing effector translocator X. citri T4S system (VirB10), H. pylori Cag T4S system (CagY), and A. tumefaciens VirB10 using ENDscript/ESPript⁴⁴ and HMM logo for loops L1, L2, and L3 displayed below the sequence using Skylign.⁴⁵ The lower panel shows the conserved salt bridge triad in the inter-subunit interface for the above three systems and the corresponding salt bridge triad in the wild-type A. tumefaciens VirB10_CTD oligomer (R242:D197:R270). Also shown for the wild type are other interacting residues involved in switching ionic interactions in the mutant G272R VirB10_CTD. Loops L1 in blue, L2 in red, and L3 in yellow, and conserved G272 and corresponding middle Gly in the GxxGxxG motif in loop L3 are shown as spheres.